Single-phase gas or vapor electric apparatus.



P. H. THOMAS. A SINGLE PHASE GAS OR VAPOR ELECTRIC APPARATUS.

APPLICATION FILED JUNE 13, 1903.

hlmfisgg Patented Sept. 15,1914.

2 SHEETfi SHEET 1.

Fig.1.

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SINGLE PHASE GAS 0R VAPOR ELECTRIC APPARATUS.

APPLICATION FILED JUNE 13,1903.

Patented Sept. 15, 1914.

2 SHEETSSHEET 2.

75 uvculfob 33 01L ammo 4 0 39 UNITED STATES P TENT OFFICE,

PERCY H. THOMAS, OF PITTSBURGH, PENE'SYLVANIA, ASSIGNOR, BY MESN'EASSICtN MENTS, TO COOPER HEWITT ELECTRIC COMPANY, OF HOBOKEN, NEWJERSEY, A

CORPORATION OF NEW JERSEY.

' SINGLE-PHASE GAS OR VAPOR ELECTRIC APPARATUS;

Specification of Letters Patent;

Patented Sept. 15, 1914.

Application filed June 13,1903. Seria1 No.161 ,282.

To all whom it may concern:

Be it known that I, PnRoY H. THoMAs, a citizen of the UnitedStates, andresident of .Pittsburgh, county of Allegheny, State of appears at thenegative electrode of a reluc tance to starting which has now been fullyset forth-in various patents'and publications. Owing to the presence ofthis phenomenon, means are required forbreaking down" the 20 initialreluctance at the negative electrode,

' and such means may be supplied by a current of high potential derivedfrom any source whatsoever and applied either to the terminals of thevapor device or to what is generally called a starting band arrangedproximity tothe negative electrode. When apparatus of this character isoperated on direct current circuits, it has been customary to apply tothe terminals of the apparatus a. momentary current of higher potentialthan that upon which the apparatus is designed to be operated. Inemploying alter-- natin'g currents, it is usual to apply a higherpotential alternating current derived from the supply circuit to thestarting band, which starting band is also preferably present in mosttypes of vapor apparatus. When the high potential current is appliedtothe start- 40 mgband, I have found that the relative phase between. thehigh tension current thus applied and the electro-motivesforce suppliedto the terminals may have an important influence on thelstarting of thelamp or otherapparatus. In practice, I have found that certain lampswill start satisfactorily with no phase difference. On the other hand,other lamps under the same or different conditions of operation, may bemore readily started by giving a lead or a lag to the high tensioncurrent and'I have found a moderate lead to be very favorable inoperating certainsizes of commercial lamps.

When the described reluctance to starting has. once been broken down,current may continue to flow through the apparatus provided the appliedelectro-motive-force is sutficiently high and also provided that thedirection of ow be maintained uniformly. When, however, currents ofvarying value or of alternating direction are applied to 0 theapparatus, the electrode reluctance is liable to be re-formed should thecurrent value drop below a certain minimum, and is certain to bere-formed when the direction of flow is reversed. Thus in operating apparatus of this class .by means of alternating currents or currentswhich vary considerably in value, provision hasto tie-made forreinforcing the lower values when the current is of uniform directionand for repeatedly 7i? Q coil in series with the apparatus which willstore energy while thei current is increasing and discharg'ethe storedenergy or a portion of it in the origihal direction of flow when thecurrent falls. With a choke coil .of sufficient capacity the risingcurrent will be suflicient to maintain current through the negativeelectrode until thesupply circuit shall again tend to increase thecurrent flow in the proper direc tion. rangement of circuits andapparatus; various organizations have been proposed for preventing thenegative alternations from undoing the work of the positives. Forexample, the amountv of ener from the choke coil is considera lylessened if a pathbeprovided for the negative alternations through theapparatus by means of a second positive electrode. With such anorganization, both the positive and negative I alternations tend to passthrough the lamp in the same direction. Meanwhile, the function of thechoke coil in delivering energy enough to supply current for the shortperiod between alternations is constantly 100 called in'tofplay." Theorganization above indicated comprises, among other features, means'fo'rstarting gasor vapor apparatus through the application of an initialcurrent of high potential, and also means for stor- 105 big energyderived from the supply circuit,

say in a coke coil, the function of which isto maintain the currentvalueat all times the energy stored on In connection with this general ar-'required above a certain minimum, so that the negative electrodereluctance may not reestablish itself. It might be supposed that inoperating the vapor apparatus upon a single phase alternating current,the capacity of the choke coil might have to be considerable, but I havefound thatin order to maintain the operation of theapparatus after ithas once been started, the choke coil need not be of excessive size. Itis desirable, however, that an extra. potential should be suppliedto-enable the choke coil inthe first alternation afterstarting to absorba sufficient amount of energy. so that it may discharge the energynecessary to maintain the lamp over the first zero point, withoutfalling below the minimum current.

It is the object of the present invention to provide means for supplyingthis extra initial potential, as will presentlyappear, it beingunderstood that the additional voltage thus withdrawn from the sourcewill'generally be removed after the "starting of the apparatus. Thismakes it possible to obtain economical conditions, during operation,

and provides that the extra potential called into use at the starting ofthe apparatus shall constitute only a momentary demand upon the system.In order to facilitate the application of the additional voltage, I- maemploy a third positive electrode or ternu- I nal, although it is not anessential feature of the invention. The current produced by thesupplementary electro-motive-force may be controlled or suppressed in anumber of ways, as by including resistance or inductance in the circuitthrough which the additional electro-motive-force is supplied; byproviding a transformer with considerable magnetic leakage between theprimary "and the secondary, the secondary being used to supply theadditional eleetro-motive-force; or by mechanically opening ordeenergizing the circuit through which the extrapotential is shpplied.The latter method is the one which is generally preferred.

.tro-motive-force, or what is called the extra;

In the accompanying drawings I have illustrated several ways in whichthe extra potential may .be obtained. Oneof these or- 'ganizationsembodies an addition to the winding of a;transformer secondary which isused to .obtain rectified alternations within the apparatus. Anotherorganization embodies'a separate transformer- ,Not'only may thesupplementary. or'additional elec :nieansjilst depotential, be suppliedby th I scribed, but this high. ten 1on-electro-motive-force whetherapplied as illustrated in Fig. 4 to the normal lamp terminals or apliedto the starting band, may be obtained rom a winding in the sametransformer as either of those referred-to or from'a separatetransformer. When using amechanical interruptionof the-circuit supplylngthe extra potential, I have found it convenient to a magnetism generatedby the current.

1 As a modification of the above apparatus, it is possible to avoid theuse of the supple mental electrode by applying to one or-both of thepositive electrodes a supplementaryelectro-motive-force and transferringthe positive electrode or electrodes to'the normal running point afterstarting, without the interruption of the circuit. The-high potential atthe starting point may be obtained, if desired, through a snap or quickyI break switch just as in a direct current lamp.

In this case it is sometimes necessary to close and open the switch anumber of times in order to insure that themechanical break should occurat a favorable ortion of the alternation for producing a lil impulse.

I haveillustrated my invention in the accompanying drawings, in which vFigures 1, 2, 3, 4 and 5, are diagrammatic illustrations of my inventionas applied to a gas or vapor electric lamp; and Fig. 6 is a diagram ofthe invention including a gas or vapor converter. In the drawings, 1 isthe container of a lamp of the character described above, the

same containing, in this instance, a negative electrode, '5, of. mercuryand positive electrodes, 2 and 3, which may be of iron. In

' gh poteptial Figs. 1, 2 and 3, I show a supplementalpositIVG-QlGQlZIOdG, 4, whichmay also be of iron. The lamp is providedwith a starting band, 6, located in proximity to the negative electrode5 and variously connected in the difierent figures of the drawings.

The supply circuit for the tween which is arranged the primary, 11, of

nected to the starting band 6 and the other lamp in Fig. I isillustrated by the conductors, 13, 13, be.-

a transformer whose secondary is shown at is connected by a wire, 8,through a choke coil, 7, to the negative electrode 5.. The conductors 13are joined to the windings, 21,

of an auto-transformer which has a supple- 1 mental winding, 14, asshown. .The winding 21 is connected at its opposite terminals electrodes2 and 3, while the winding 14 is by means of wires, 9 and 10, to thepositive joined by a Wire, 22, to the supplemental joined to the saidwinding. The conductors electrode 4. At the mid-point between the Iterminals of the winding 21, the wire 8' 1s source'ofsingle-phasealternating curren t,' v 4 and when the circuit of the sald source isclosed, throwing potential on the primary 11, the secondary wind ng 12-re-- ceives a high ,voltage, whichis impressed;

upon the'electrode 5 and the starting band '6 insuch a way as strain at,the surface of the. negative electrode, breaking down its resistance toproduce a 'critical nuance allowing the positive potential .and one ofthe electrodes 2, 3 or4 tostart the lamp intooperation. The operation ofthe lamp is then as follows: Assuming, for example, that the electrode 2(neglecting the electrode 4 for the moment) has a positive potentialwith regard to the negative electrode at the time of the-application ofthe critical strain, current-flows from 2 to 5, reaching finally theproper value for the electro-motlve-force supplied and at the same timestoring energy in the choke coil 7. During the latter part of'the firstalternation, as the voltage upon the positive electrode 2 falls to zero,

the energy previously stored in the choke coil 7 continues the-flow ofcurrent inthe.

, original direction through the coil until the potential upon theelectrode 3 becomes positive in its turn, whereupon electrode 3 willtive in the third alternation, when it is utilized to again support thecurrent through the lamp and the choke coil 7, and so on, as long as thelamp operates.

The function of the supplementary winding 14 and the supplementarypositive elec-" trode 4 is to supply an additional eleetromotive-forceduring the alternation within which the critical or starting strain isapplied. It is evident that during this first alternation, the currentmust reach its maximum value after starting from zero, where- I as, whenonce the lamp is operating normally, this maximum current must bereached in one alternation, startlng, not from zero, but from theminimum value reached during the operation which must at least betheminimum operating current of the lamp." Once the negative electroderesistance of the lamp is broken down suf ficiently to allow anoperating current to pass, the extra voltage upon the supplementarypositive electrode 4 is no longer required and in fact will cause awaste of energy and a disturbance of the operation of the lamp andshould be removed from further operation. This disturbance of the excessof current tending to flow from the extra potential upon thesupplementary electrode 4 provided no restraining devices are used. Suchdisturbsnce of the operation may be avoided, howe er, by the insertionof an i-nductanee device or resistance, 23,

which may, as Fig. 1, conveniently be placed in the circuit of thewinding 14. The action of the inductance device or resistance 2.3 issuch as to prevent an excessive flow of 1 current after the apparatushas started into operation, at thesame time allowing the full voltage ofthe source to assist'in the overcoming of the negative electroderesistance since unless the current flow actually increases novoltageyvill be absorbed upon the inductance deviceor resistance 23. Theimpedance-23 is so proportioned as to allow only a very small current toflow when the apparatus is in 'operation. When the apparatus isto bestarted, however, since no current flows through it, the full ,potentialof the supplementary transformer winding is impressed between theelectrodes in the apparatus. It is this tension strain backed by thepower of the main positives to deliver currentwhich breaks down theelectrode resistance. Enough current must, of course, be allowed to flowthrough this impedance 23 when the apparatus is in operation toestablish 'an initial current, in the choke coil 7.

Referring to Fig. 2, the transformer primary 11 is connected between oneterminal of the coil 14 and the conductor 8. In the circuit of theprimary is included the movable element of a switch, 15, whichconstitutes an armature for the choke coil 7 The winding 14 and theoperation of the lamp would result from the a the supplemental electrode4 1s here omitted,

andthat the conductors 9 and 10 are j oined organization illustrated inFig.2 is in other respects similar to that shown in Fig. 1, ex-

system as soon as the operation begins. It

is clear that when the supply circuit is closed and current is caused totraverse the primary 11, the secondary 12 will be energized, as before,and the choke coil will also receive current. In response to thedescribed action, the movable element of the switch 15 will be Withdrawnfrom contact with the stationary element thereof and the primary 11 willbe cut out. o y l v In Fig. 3 the extr-a potentialapphed to the lamp issupplied by a transformer 24, 25, the latter being the secondary andhaving its respective terminals connected to the supplemental electrode4 and to the -elec-. trode 5. The other connections are shown clearlyupon the drawing. In this arrangement of .eircuits I may. include theinductance or resistance 23 in'the' circuit of the primary 24, itsflmctions being the same as already described in connection with Fig.1.-'

Referring to Fig. 4, it will be noted that to the windings of theauto-transformer 21 starting band is connected by -a wire 26 with theconductor 9,while ashunt circuit 27' .containing a quick break switch16-and a resistance 17 (which maybe in the form of an inductance deviceor reactance-coil) is connected between the conductors 9 and 8.

In this figure the switch arm 19 at the left is represented at startingposition, while' the corresponding arm at-the right is represented ashaving been moved from the starting position to the opposite extremeposition. An extra winding 14 is here added at both ends of the winding21, and each is connected through one or'the other of the adjustableresistances to a separate positive electrode in the'lamp. Withtheswitches in the starting position, the supply circuit '13, 13 isclosed and the snap or quick-break switch 16 is operated. By the actionof the switch 16 and the choke coil 7, a high poten-' tial impulse iscreated at the starting band and this is reinforced by the energydeveloped in the windings 14, 14. The lamp 3 having been once startedinto operation inopposite in phase.

this way, the switches 19 are moved from the starting position to theoperating" position. (the latter being illustrated, as alreadyexplained, by the switch at theright hand side of Fig. 4) and theoperation continues with the windings 14:, 14 disused.

In the figures already descrlbed, there are impressed between theneutral point and the two main positives, respectively, two alternatingelectro-motive-forces exactly These are obtained by connecting theneutral point of the supply circuit 'to the negative electrode andutilizing the supply mains as the two positives.

' In Fig. 5 the same result is attained in a slightly difierent mannerwhich allows the full line voltage to be impressed between the neutralpoint and one positive. In this figure, as before, we'have two exactlyopposite electro-motive-forces impressed between the negative electrodeand the two main positive electrodes of the lamp. One of these is thesupply electro-motive-force.

itself, the other is a similar electro-motiveforce obtained by means ofa transformer which allows'its direction to be reversed. It is evidentlypossible to utilize another winding, as 14, ,up'on the same core as the22, thus practically deen'erg'izing that part amazes of thecircuit.":In'thisfigure I also show means forcreating a phase differencebetween'the current applied to the starting band 6 and that applied tothe supplementary electrode 4. In practice, I find it advantageous togive to the current applied to the starting band a slight lead or lag,depending upon the circuit conditions. Such a lag can be accomplished,asfin Fig. 1, by

means of a spark-gap such as is shown at 35 oreither a lead or a lag maybe secured by such means as are illustrated in Fig. 6,

Where the primary 37 of a transformer, 36, a

is coupled up between the supply wires 13, 13, while the secondary, 38,is connected between one of the conductors 13 and the startingband 6. Inshunt to the primary I may arrange a resistance, 39, and in series Itherewith an inductance, device, 40, the same being so proportionedas/to give the news sary lead orv lag to the secondary current. Thearrangement shown is so devised as to give a lag to the secondarycurrent, whereas- 4 by reversing the position of the resistance 39 andthe inductance 40, a lead would be given to the current. Thecurrent'fiowing through .the coil,'40, lags behind the electro motiveforce of the mains, 13, in virtue of the inductance of this coil.After-traversingthe coil,

40, this current divides in two parts one.

through the winding, 37 this part constituting the magnetizing currentof the transformer, 36, and the other part traversing the resistance,39. Since these two branches are in parallel, they musthave the samevoltage impressed upon them. Now, since the branch, 37 is inductive andthe branch, 39, is non-inductive, relatively speaking, the current in 37will lag behind the current in 39. Therefore, since the current in 4:0lags behind the voltage in the mains, 13, the magnetizing current in 37will lag still farther behind. If, now, a resistance be substituted forthe coil, 40, and an inductance be substituted for the resistance, 39,wehave a different condition. In

this case as far as the resistance is concerned, the phase of thecurrent therein is the same as that of the mains 13. The current throughthis resistance will as before divide into two parts, one parttraversing the magnetizing winding, 37, and the other part traversingthe coil which has replaced the resistance, 39. If, now, there be adifference in the power factor between the winding, 37 and the coil inparallel to it, as there will be in actual practice if the coil be madeas shpwn' at 40 with an open circuit magnetic core (thus producingapproximately 90 degreeslag), the current in the magnetizin winding, 37will be in advance of that in t e winding, 39, therefore it will be inadvance of the electro motive force of the mains, 13, since theresistance in place of the coil, 40, will keep the total current inphase with the voltage, 13. The form of vapordevice illustrated in thisfigure is that of a converter, being different in this respect from thedevice illustrated in the other figures.

It is known that the .critical strain may be applied to the apparatusthrough other instrumentalities than the starting band, and if desiredany means equivalent to the starting band may be substituted therefor.

In a divisional application filed by me August 11, 1903, Serial Number169,091, claims are made upon the apparatus described herein.

I claim as my invention:

1. In a system of electrical distribution the combination witha"mercuryvapor apparatus requiring a critical starting strain, analternating supply therefor and means for impressing such criticalstrain upon such apparatus, of means for varying the relative time ofthe application of said critical strain, such means including apotential raising transformer and an exciting circuit thereforconsisting of phase controlling means in series with the transformerprimary across.

the alternating current supply and a second phase controlling. means inshunt thereto.

2. In a system of electrical distribution the combination with a mercuryvapor apparatus requiring a critical starting strain, an alternatingsupply therefor and means for impressing such critical strain upon suchapparatus, of means for varying the relativetime of the application ofsaid critical strain, such means including a potential raisingtransformer and an exciting circuit therefor together with an inductancein series therewith across the said source and a resistance in shuntthereto.

3. A starting system, comprising a mercury vapor device, a cathodetherein, a starting band for applying a critical strain to said cathode,a transformer for applying a high voltage-to said startin band and meansfor supplying said trans ormer from the mains supplying the vapor-deviceand means f /varying the phase' of current supplied by said transformerrelative to the supply circuit. I

. 4. A starting system comprising a mercury vapor device, a cathodetherein, a starting band for applying a critical strain to said cathode,a transformer for applying a high voltage to said starting band andmeans for supplying said transformer from the'mains supplying the vapordevice and means for varying the phase of current supplied by saidtransformer relative to the supply circuit, said last named meansincluding resistance and inductance in shunt and in series with theprimary Winding of said transformer. r

5. A starting system for a mercury vapor apparatus having a cathoderequiring a critical starting straln, comprising means for applying ahigh voltage impulse to said cathode, said means including a transformerconnected to the source supplying said vapor electric device and meansfor controlling the phase of the voltage of said transformer, such meanscomprising serially connected devices for determining the general phaseof the magnetizing current of said transformer and a shunt circuit ofdifl'erentcharacteris tics from said primary winding for adjusting thephase of the current in said primary winding to lag or to leadas'required.

6. A starting means for a mercury vapor apparatus having a cathoderequiring a critical starting strain, comprising means for applying acathode, said means comprising a transformer connected to the sourcesupplying said vapor .electric dqvice and means for controlling thephase of the voltage of said means comprising an inductance in serieseral phase of the magnetizing current of said transformer and a circuit0 different characteristics from said primary winding for adjusting thephase lag of'the current m said primary winding to lag or to lead asre'uired.

igned at'New York, and..State of of June, A. D. 1903. I

-. PERCY .H. THOMAS.

. Witnesses:

Tnos H. BROWN, Jr., Gnonen H. STOGKBRJDGE.

York, in the county of New New York, this 8th day high voltage impulseto said

